Isolated Worlds
of the Tepuis
Remnants of vast sandstone
plateaus called the Roraima
group, tepuis are natural lab
oratories for studying the
adaptation of species to severe
environments. Isolated from hu
man horticultural tampering,
they hold clues to naturalplant
succession and dispersal in
habitatsrangingfrom rocky
outcrops to riverine forests.At
leasthalf the estimated 10,000
plant species here are unique
to the tepuis and surrounding
NationalGeographic, May 1989
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